Weeders for pulling out weeds growing in farms and gardens are disclosed in, for example, JP H6-046604 A, JP H6-269201 A, and Japanese Utility Model Publication No. H6-044390.
The “weeding device” disclosed in JP H6-046604 A is targeted to “efficiently pulling out grass along with the root, to improve the lifetime of teeth”. In order to achieve this objective, a structure is employed in which “a plurality of teeth are provided in a line on a drive shaft and spaced from each other”, “adjacent teeth are periodically opened and closed by a slide key”, “the tooth in the closed state is driven in a direction to pull out”, and “grass is held between teeth that are periodically opened and closed, and the tooth in the closed state is rotated for a while so that the weed can be efficiently pulled out from the root even for the weed of low height”. The “weeder in lawn” disclosed in JP H6-269201 A is targeted to “develop a weeder which can pull out and remove, from the root, weeds growing in the lawn without damaging the lawn”. In order to achieve this objective, a structure is employed in which “one of a machine frame surrounding in a rectangular shape is extended upwards to form a handle section, a free-moving front wheel and a free-direction, free-moving rear wheel are provided on a front side and a rear side of the machine frame, and two rotational blades which are driven by a motive force from a motor are provided on left and right at an intermediate position of the front and rear wheels”, “the rotational blade is supported by a rotational plate and rotational plate supporting arm mounted on a grooved pulley, is held between a rotational blade opening and closing member and a rotational blade supporting member fixed on the shaft, and is slid and rotated”, and “the rotational blade opening and closing member causes the two rotational blades on the left and right to function to open or close while the angle is changed according to the rotation, and only the weeds in the lawn are weeded by lowering the rotational blades into the soil”. The “weeder” disclosed in Japanese Utility Model Publication No. H6-044390 is targeted to “provide a new means for efficiently removing weeds growing in the lawn with a mechanical means while distinguishing weeds from lawn, in a manner to pick up the weeds”. In order to achieve the objective, a structure is employed in which “a rotational member which rotates using a lateral shaft is laterally placed and pivotally supported on a mechanical structure which travels by a travelling wheel, and a comb-like member in which many spike-teeth are placed in a line and with a spacing to allow leaves of the lawn to pass is mounted on a peripheral surface of the rotational member in an inclined state toward the front of the rotational direction of the rotational member and in a manner such that the lined spike-teeth of the comb-like shape pull out the growing weed while combing the leaves of the lawn by the rotation of the rotational member”.
The “weeding device” disclosed in JP H6-046604 A is a handy-type weeder, and a motor which operates by a battery is employed for the motive force. The “weeder in lawn” disclosed in JP H6-269201 A is used while being towed by a tractor or the like. The “weeder” disclosed in Japanese Utility Model Publication No. H6-044390 is a machine targeted to be used for occupational activities, as the engine is used for the motive force.
However, with the “weeding device” disclosed in JP H6-046604 A, the weeding operation must be performed while the operator bends his lower back, which becomes a burden to the lower back. In the “weeder in lawn” disclosed in JP H6-269201 A and “weeder” disclosed in Japanese Utility Model Publication No. H6-044390, the structure inside the machine is complex, the maintenance is not simple, and the use of these devices in homes and farms is too luxurious and unsuitable.
Therefore, the Applicant has diligently researched for developing a weeder which can efficiently pull out the weeds growing in the farms and gardens along with the roots, which have simple structures, and which can be easily used in homes. Some results of the research are disclosed in JP 2006-129854 A and JP 2008-086301 A. A “weeder” disclosed in JP 2006-129854 A is targeted to “provide a weeder which pulls out, removes, and mows weeds mixed in a lawn by a clip which moves up and down”, and employs a structure in which “pulling out, removing, and mowing of the weeds or the like are enabled by opening and closing movements of the clip which moves up and down, and the structural function of the clip is changed to enable various tasks”. A “weeder” disclosed in JP 2008-086301 A is targeted to “provide a weeder which pulls out, removes, and mows weeds mixed in a lawn or the like by a clip which is equipped on a rotation drum”, and employs a structure in which “pulling out, removing, and mowing of the weeds or the like are enabled by opening and closing movements of the clip equipped on the rotation drum, and the structural function of the clip is changed to enable various tasks”.